3.20编程打卡

*6.4（反向显示一个整数）使用下面的方法头编写方法，反向显示一个整数：

public static void reverse(int number)

例如：reverse(3456)返回6543。编写一个测试程序，提示用户输入一个整数，然后显示它的反向数。

import java.util.*;

public class o {
    public static void reverse (int number) {
        int eve,ano = number;
        int reverse = 0;
        while (ano != 0) {
            eve = ano % 10;
            reverse = reverse * 10 + eve;
            ano /= 10;
        }
        System.out.println(reverse);
    }
    public static void main(String[] args) {
        Scanner input = new Scanner (System.in);
        System.out.print("请输入一个整数：");
        int number = input.nextInt();
        reverse(number);
    }
}

 6.5（对三个数排序）

import java.util.*;
public class o {
    public static void displaySortedNumber(double num1,double num2,double num3) {
        double max,mid,min;
        max = (num1 > num2) ? num1 : num2;
        max = (max > num3) ? max : num3;
        min = (num1 > num2) ? num2 : num1;
        min = (min > num3) ? num3 : min;
        mid = num1 + num2 + num3 - max -min;
        System.out.println(max+" "+mid+" "+min);
    }
    public static void main(String[] args) {
        System.out.print("请输入三个整数");
        Scanner input = new Scanner (System.in);
        double num1=input.nextDouble();
           double num2=input.nextDouble();
           double num3=input.nextDouble();
           displaySortedNumber(num1,num2,num3);
    }
}

 6.6（显示图案）

import java.util.*;
public class o {
    public static void displayPattern(int n) {
        int i = 0;//行数
        int k;
        for( ;i <= n;i++) {
            for(k = 1;k < 2*(n+1-i);k++ ) {
                System.out.print(" ");
            }
            for(k = i;k > 0;k--) {
                System.out.print(k + " ");
            }
            System.out.print("
");
        }
    }
    public static void main(String[] args) {
        System.out.print("请输入一个行数n：");
        Scanner input = new Scanner(System.in);
        int n = input.nextInt();
        displayPattern(n);
    }
}

 *6.7（财务应用程序：计算未来投资价值）

import java.util.*;
public class o {
    public static double futureInvetmentValue(double  investmentAmount,double monthlyInterestRate,int years) {
        double investLater = investmentAmount * Math.pow((1+monthlyInterestRate/1200), years * 12);
        return investLater;
    }
    public static void main(String[] args) {
        @SuppressWarnings("resource")
        Scanner input = new Scanner (System.in);
        double  investmentAmount, monthlyInterestRate;
        int years,i;
        System.out.print("The amout invested:");
        investmentAmount = input.nextDouble();
        System.out.print("Annual interest rate:");
        monthlyInterestRate = input.nextDouble();
        System.out.println("Years	Future Values");
        for(i=0;i<31;i++) {
            System.out.printf(i+"	%.2f
",futureInvetmentValue(investmentAmount, monthlyInterestRate,i));
        }
    }
}